Motor-vehicle.



PATENTED AUG. 1s, 1908. LO. HOFFMANN.

MOTOR VEHICLE. APPLICATION FILED-SEPT. 26, 1.907.

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PATENTBD AUG. 18, 18.08.

E. G.. HOFFMANN. MOTOR VEHICLE.

APPLIOATION FILED SEPT. ze, 1907.

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E. G. HOFFMANN. MOTOR VEHICLE.

.APPLIOAIVIION FILED SEPT. 26, 1907.

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gmvenioz' v @Hof/14mg! nnrrnn s'rnrns ERNST (,RL'STV HOFFMANN, OF. NEW ROCHELLE, NEW YORK.

Moron-VEHICLE.

Specification of Letters Patent.

Patented Aug. 18, 1908.

Application tiled September 26, 1907. Serial No. 394,60@

To (1U w71 om 'ii 11mg/ concern.'

Bc it known that I, E'nxs'r GUsrAv HOFF- MANN, a citizen ofthe United States, and a Uiiited States filed September 16, 1907, and

Serial No. 393,048an im roved vehicle driving mechanism is set fort in which there are two electric motors mounted upon the vehicle body and between the driving wheels,

' which motors are directly connected with their reslpective driving wheels by a shaft, universa connections being provided at each end of each shaft to permit the shafts to 0scillate freely as the body-'moves with respect to the driving wheels, and the shafts being lengthened b extending them into the respective driving wheel hubs or into the respective motors in order to reduce the eX- tent ofthe oscillations of the shafts. In that improved driving mechanism, the electric motors are rigidly mounted upon the vehicle body.

The present improvements relate to the driving mechanism just referredto and the object of these improvements is to securethe motors upon .the vehicle body in suchia way that they may oscillate freely in a vertical plane and have at least a small movement in the direction of the axes of rotation` of their armatures. In this way, the universal joint at the inner end of each intermediate shaft may be eliminated and moreover there will be no need of providing a sliding joint in the intermediate shaft, such as is necessary in the driving mechanism referred that the motor shall be capable of having oscillations in a vertical plane and of moving slightly in a longitudinal direction.

` The improvements are applicable to .what may be referred to as any direct driving system, that is, any .system in which the motor is directly connected with its corresponding driving wheel by means of an intermediate shaft 'without the interposition of clutches, gearing, or anythin of the kind;

and while inthose cases it wil be desirable to extend this intermediate shaft inthe inanner explained in the application hereinbefore referred to, the present improvements may beemployed where the intermediate shaft is not so extended. In vehicles which are constructed to run upon rails the relativeI motion between the axle or driving wheels and the vehiclebody is generally very .small and is certainly much less than the relative motion between these parts in road vehicles, and the present improvements are particularly applicable in cases where the relative movement between the body and-drivingwheels is small such as in railroad cars, trolley cars, and the like. l

Besides compensating for the relative movement between the vehicle body and wheels, the present improvements act .to conserve the vehicle springs in that the gyratory effect producedv by the inertia of the vmotor armature tends to oppose the oscillations of the motor and therefore, as will be seen, the construction possesses what may bereferred to as shock absorbing qualities. Moreover, as the force tending to oppose thel oscillations ofthe motor is proportional to the speed of the armature, the shock absorbing qualities are proportionately greater as the vehicle increases its speed, and thus areautomatically adjusted to the needs of the vehicle at any given moment.

The invention will now be more fully de scribed in connection with two embodiments thereof which, for purposes of illustration and explanation, are shown in the accompanying' drawings.

broken away, of the driving mechanism of a motor road' vehicle in which the improvements have been applied. Fig. 4 is a' detail view of the same mechanism, and Fig. 5 is a 5 view similar to Fig'. 3 with some of the parts removed, to show the manner of assemblage. In' the embodiment of the invention illustrated'in Figs. land 2 of the drawings the ably formed and suppprted as described in an application for U. Si Letters Patent filed {March 27, 1907 and Serial No. 3'64,923,"being received at each end inthe guide blocks b and .having a suitable ball bearing provided at -eacl end between said shaft and an extended portion e of the usual flanged wheel e. The two motors g are provided between the wheels e upon each end of the shaft c and are supported on the truck frame a so as to be -capable of oscillations in a vertical plane extending transversely of the vehicle and to have at least a slight movement in the direction of their armature shafts, that is in a longitudinal direction with respect to said shafts. For this purpose each motor is provided with a pair of trunnions f one on each side of i its casing, and these trunnions are j ournaled in arms f pivoted to and depending from the truck frame a, such arms preferably having long bearings f2,as shown in Fig. 4. The shaft c extends through both motors,

and the armature shafts g ofthese motors are made hollow for this purpose and sufficiently largeto permit the vertical oscillations of the shaft c to take place.' The outer end of each armature shaft g is connected to the corresponding wheel eby means of a iexible joint h, one terminal member of 15v which is secured upon the periphery of this shaft and the other terminal member being secured to the inner side of a ange e2 secured to the wheel e. It will thus be seen that as the truck frame a moves up and down with respect to the wheels e, the motors g will have slight oscillations in a verticalv plane and a slight movement in the direction of their armature shafts, while the connection between the armature shafts and driving'wheels permits the latter to be driven directly by the oscillating motors without any lost motion or without any interference in the transmission of power as these oscillations take place.

In Figs. 3, 4 and 5 where -the invention is illustrated as applied to a motor road vehicle, thevehicle body is indicated at a and the motors g are supported from the vehicle body in the same manner as has just been described with respect to the motors g in Figs. 1 and 2. The driving wheels e3 howsesgos l evervare supported upon hollow axle ends e4 which are rigidly secured to the main axle c2. 'The armature shafts g2 of each motor are c xtended through the hollow axleV end e4 into the'wheel hub, and, as shown in the drawings, are connected to the outer end of the wheel hub by means of a `flexible joint e5, such shafts being extended in order to lengthen them and reduce their oscillations, as explained more particularly in an application for Letters Patent, filed June 8, 1907 and Serial No. 377,851. j

Itis not necessary to describe the details of construction of the wheel hub, flexible joint and the like, for they form no part of the present invention and moreover they are set forth in detail -in the application just referred to. Fig. 5 illustrates the method of assembling these parts, and from this figure itwill besee'n that the extended portion of the armature shaft gv2 comprises al short intermediate shaft gv3 which is secured to one-teri lminal member of 'the universal joint e5 and is inserted through the hollow axle e* and secured to theshaft g2 Aby means of a suitable 90 .coupling iece g4. A cap eyis provided for the end o the wheel hub'in order to hold the parts in osition.

It wil be understood `that the improve- -rnents may be applied to road vehicles with-` out extending thel motor shaft into lor through the wheel hub, this construction being referred toin the present case as being possibly the preferable one and as Afurnishing a simple basis for explaining vtheapplication of the improvements to a motor road vehicle. It will be easy to understand the effect of the gyratory action of the motor armatures upon the spring system, for it is obvious that `When the armatures are' in rotation', any

force tending to change theplane of rotation y of the armatures,such as is produced by the relative movements of the vehicle body and, wheels, will be resisted by a counter force depending upon the speed of rotation of the armatures.v -Referringparticularly to Figs. 3, 4 and 5, it will be seen that the connection gf between the motor armature and the corresponding driving wheel affords a means of deflecting the plane of rotation of the armature when' any relative movement between. the vehicle body and wheels occurs, whereby the counter force referred to is produced. The result of this counter force will be a steadying effect 12o upon the vehicle springs tending toward a smoother running of the vehicle and substantially reducing the possibility of damage to' the springs. Vfhen the vehicle is being driven at high speed the gyratory force will be considerable and will obviously' act as a shock absorbing medium and when the speed is decreased, the gyratory force will alsodecrease, gradingitself automatically with the s eedv of the vehicle. If the motors are run at igh 1 speed, itis preferable to mount the motors so that they may displace themselves in a direction lat right anglesA to Atheir plane of oscillation, that is in a direction lengthwise of the car or vehicle,.on acco'untof the tendency 'to swerve which the motors have when runat high speed and oscillated. For this purpose springs g are provided between the relatedtov the driving'mechanism, the vehi cle body and Wheels in order that .the gyratory effect of the` retation of their armaturesV may be availed of to perform the functionsjust described. Moreo`ver, the improvements are capable 'ofi various other embodiments besides those shownfand described herein.. j Finally, in order that the statement in .the

4first paragraph of thespeciiication to the 'effect that the improvements are applicable-to a d1rect drive system, may not be misunderstood, it should be mentioned that the motor lo'r other drivingnelement may of course be provided With reduction gearing or the like or the 'same may bejntroduced between the motor 'and 4driving'wheel or Wheels without interfering with the results which the prese`nt improvements are designed to effect. In`

other words, where it is desirable to employ a high speed motor and to support the motor and transmit the power to thedrivingwheels in accordance withithe, invention .set forth and described herein, reduction gearing may,

be Iemployed and may, if desired, be embodied with the motor in such-a way-as to partake of its oscillatory motion.

I claim as my invention: ,1. In a motorvehicle, the combination of a driving wheel, an axle for the Wheel, a driving element, a support for the driving element having relative movement with the axle, a shaft operatively connecting'the driving ele- -ment and wheel, means to suspend the driving element from the support so that it may have oscillations in a vertical plane and movement substantially in Vthe direction of the shaft., and a flexible coupling between the shaft and wheel. y l L i 2; ln a motor vehicle, the combination-of a driving wheel, anaxle upon which the wheel is journaled, an electric motor, a support for the motor having relativemovement with the axle, a shaft between the motor and driving wheel operatively connecting the motor and wheel, means to suspend the motor from the support so that it may have oscillations in a vertical plane yand movement substantially in the direction `of the shaft, and a universal coupling between the shaft and driving wheel. n, 3. ln a motor vehicle, the combination of 'a ldriving wheel, an axle upon whichv the Wheel is journaled., a driving element, a support for they drivlng element having relative movement with the axle, a shaft operatively connecting the driving element and wheel, arms pivoted upont'he supportv a nd depending therefrom, trunnions upon the motor oscillate in a vertical plane and have move- .ment in the direction of the axis of its armature, the armature shaft being extended to the driving wheel, and a flexible coupling between said 'shaft' and driving wheel.

5. ln a motor vehicle,'the combination of an axle,l driving wheels at either end thereof, a vehicle'body having relative movement with the axle, a motor, flexible means to connect the driving shaft of the motor with one of the driving wheels, and means to support` the motor so that it may have oscillations in a vertical plane and movementsubstantially in the direction of its axis. l

6. In. a motor vehicle, the combination of an axle, driving wheels thereon, a vehicle body spring' connected to the axle, an electric. motor for each driving .wheel rovided with trunnions, means depending rom-the body in which said trunnions are journaled to permit the motors to swing freely in verticalplanes and to move longitudinally in the direction of the axes of their armatures, and 'flexible' means to connect the driving shaftsof the motors with their respective driving wheels.

7. In a motor vehicle, the combination of 'an axle, driving wheels journaled thereon, an -electric motor for each driving wheel having a hollowarma'ture shaft through which theaxle is extendpd, means to support `each motor so that it may haveoscillations in a vertical plane and movement in alongitudinal direct1on, and a flexible connection, `between each motor and; its corresponding driving Wheel. l

8. In a motor vehicle, the combination of driving mechanism containing a rotating elel ment Amounted to permit deflection of its plane of rotation, the vehicle body, the veicle wheels, the vehicle springs between the body and Wheels, and means to deflect`the plane of rotation of the rotating element as the .springs are compressed or expanded.

9, In a motor vehicle, the combination with the vehicle body, vehicle wheels and vehicle springs, of an electric motor mounted upon the vehicle body and capable of oscillating thereon, and a connection between the motor and one of the wheels adapted to cause the motorl to osoillatewhen the body and Wheels move with respect to each other, in order that the gyratory eii'ect of the motor armature may oppose the rela-tive movement of the body and wheels.

10. In a motor vehicle, the-combination with the vehicle body, vehicle Wheels and vehiole springs, of an electric motor mountedv upon the vebiclerbody and capable of oscilloting thereon, n connection between the motor and one of the Wheels adapted to cause the motor to osoillate when the kbody and Wheels move With respect to each other,` and yielding means to resist lthe tendency of the motor to swerve when the axis of rotation of its armature is deeclted by the relative movement of the body and Wheeis.

This specic ation signed and witnessed this 19th day of September A. D., 1907.

ERNST GUSTAV HOFFMANN. Signed in the resence of#- LUoIUs VARNEY,

AMBRosE L. OSHEA. 

